SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '90eda0e5bb4b2cdfb1c73e1859550ac66ecd4a35ddb05b4690810980e3636b57' 
  AND token = 'IVwTA7ODyySfD5S9JL4gdQ8H7JuxytCyyLacCSTkkRU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}