SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d3b435f608c9db9697a35081538d053fb8e1384e2945e12e77f411a93ecbb50' 
  AND token = 'BCg8zHQ6/9fAk/+0mT3xqT8o05vROyYc7B9tLSqan8g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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