SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0482ce84d18a145dd5b51bab39943bd74262c343b990b25549786bceac0aba38' 
  AND token = 'Fz8SYNSgd32tIe5a4B8KHObPYwqk44jA/vb3Z1UIRus=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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