SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1fe0897ad7832cb49dc087ea1e7b5f06dfb5d18bb0441424e326bf18cec0672d' 
  AND token = 'Eh3WOAr6EksbjEdzZ2lzcuSQSWA0zN7YC8ER43Q0zr8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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