SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b06b53f5a6c88713cf5f57194748e7feeca6ac0ddbe9dc9a603061737f65f92' 
  AND token = 'aMT1+X+ZQoc8ocbqeuQgbVqZ3e48p4VvYcDbqdZIv/o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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