SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6266bc21fd423655610a3d4495a8c755069a262ddbfba72ba31ffcff6df30053' 
  AND token = 'pFHlLM6rA44n7tkNPoWyIerKzHorJ49t2uNaE9xQ+Kc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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