SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aac315525f176841c4c2c4e9854d2781cb9d74f6c3e9daede7c6ce057a7e635f' 
  AND token = 'INb0a/pnaSyGGhb2wrvDxobdHwyOYB7RoAS1IHASzIQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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