SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e636022bf97d1fb8cc86774430924aad7c464530b752e8251dfaa8aa5907c8d4' 
  AND token = 'cbYyiIDHE3otkI80gn87uy9ld4dUPfK3gnPAV2oJPaA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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