SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1b96f8dbfe96be2094e54d827cf91128e78d2e409967efb3a9ef4b5b749d6bf5' 
  AND token = 'oh/wPIP9ONgHSLPJYnolJbJnQiHjf4/ZqgHrw86kV24=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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