SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0941a595efc03572dc0f5c62944744067fbec0342825c46ebcf5bd48cb23d502' 
  AND token = 'bF2o+Wf5NJGeS8eIPUXKw5G800Ju507AfIwQbUQHklA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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