SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e72073738af89f5c6c2dd99ff6c67dcf698bb4473c07b4efa1f8053b31cdada' 
  AND token = 'nkMTXc7muUjJRxW1vQp6iF9RDXav9FmhxWMECSGYHAw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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