Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3caa7b3e45bf105cb0103c6d04a6c4539dc282f0e4568ada4480ff52264f6626' 
  AND token = '2mLLQ0tY0yVb8xCBfPqdbEvyVC64KGUcHF9BsC1usJQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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