SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bcd0f739b05148b05509e042b3c42fe68faa36f68a7af2632ff675921fb6b243' 
  AND token = 'ALyv8PAANtNWPjTdQ7xX/kPQ89zaXmVwpGkN54Y5H6U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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