SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea527dd6f84c3415dd1fb6ad65a0c118096be8819968aeb199d879648f9f5784' 
  AND token = '2qyyivgZ7XUZR39nU21iUBjgv2afUfQYokqwIGlNdso=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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