SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bf212ed06ed4c6d1fe22b0bfa8dc17fb0e17f8b43cb01e87159e043b6da0e05a' 
  AND token = 'AvYlNTwWj00iApIzCPNK+qTeUDmVmGyGAW/jzKn2rZI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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