SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '218cbbd2f190e42bf711a723f71ca7145eef65599919bcc950a4a4057b94535b' 
  AND token = 'gEELdTbuDD98+Tq95q/sjdUPD05HfFqBsISgxjWn0WE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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