SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f95fae67a123d4a05bec8a54ddcda6e81a6b857a3268383115dcf39da80d01ab' 
  AND token = '9HUYUF7I3YUBrMxx1zgcdfPTqN+WE/ATtBib7YJxxiw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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