SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c96c7ca847844fe2ac458e27da6140149fd9b4e03718838e66a2fb0ebba3a157' 
  AND token = 'P1ILFMD112AVyrJJYCEC1LtPe3aZ5WpcL4TlHwTEjFs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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