SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8aa30fb3ecf31e26bfde90c273eadc9aef2faf714ae9c77b759762624ef3a783' 
  AND token = 'fdWEkwRSLhyE8hEcuTf1OP7xV/N6GamaPdTR5+1pKlU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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