SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'ecbf7d422f20bd2ab8f9134b2386007abbcf6fddfffa2757b27ffc637614faca' 
  AND token = 'lx4b8BI+Rc2klgSS1JNVEiTxNTqfuLLiqSFdjySf898=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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