SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1124f17c49ba54cf16387d91550c9f766f070794bead095fef475f15f0a2faa9' 
  AND token = 'JDrg8wUELVJerWtFL5rl3E1bO5ry3JoKPMWNX/Q4F5M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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