SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc7c430b59bb5be44bff24198c0a0152fe2a9bdc7c335e073682c202d2d259bf' 
  AND token = 'nZQmXJs+19eN/jFc8XGmAZi6PHqVEx0hCAKfSqx6n60=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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