SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c3c02b90bf605d3ff04658ff9c9865a37d146ce919957e33c26e5ee38250220' 
  AND token = 'Tw1E1jaCuohwlKmwRZ5p835T4CK3iApE+48BOGCyIQY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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