SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c52c7f2b18c962f9ef29420d95bf3f5cccc375d881932c8379ea61ef899589e' 
  AND token = 'W/IYN2sWg8k7QyNjy+zxGYYc66tNKtEr//JeDO8o3TA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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