SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b31588322ec6cb78232fba41365262d30c1c9c0d0be4248ec1739d9973722ef3' 
  AND token = 'wzov3UN0HiYvlVyomSBFL1uLQpUGjYfueYHPdfSAIWQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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