SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8ac038a8aac70a2fb3fb91ee486e59dd8982de2b7fc9ac36902aa846e51f0eaa' 
  AND token = 'wdWuxWvNyN5P/P9evEN5JJlauPCnc1LKSdpUf9FJWRM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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