SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0fccc204cbd7e313990696de80453580fe2c8d23915cd430b87dde932a0c707a' 
  AND token = 'Rv4OP8X5xhIXGojPMPK61iB3hMGglsHnv84EnPRFsAg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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