SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a0b977501fee3732ebc598188b7757a7ebf3a211915bf4c27257c930e0752f44' 
  AND token = 'tZnaKeUvIsHYIGHjuYFyDxZue3LM1DQvsCK8s/w0Pv4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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