SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ba7a2b4d809fe9070c4cc9385023a19e69d474fc788cc3066e984d57a42e546' 
  AND token = '/ZmEm5fo36qmw/FwsRNAmDpt+eOqgeHnI79gUfqBuF0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}