SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de4524d62930b452a335cad34c902fc8895bc5af4b5df180ec70245382d37297' 
  AND token = 'yWNUQhuWwdcr6Rk80vCXKIQQaNdKeQzZ8PKe6KWAOtk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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