SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f6e3a3adfaddb0c24770e3356e99bfda0fe9a2e6e18463387088c34ada0ad6a7' 
  AND token = '+430Tdf93mrncY/PtqS+bcsd4FfJMwiHUJEfYHpNGt0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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