SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a5d4aab6c8612e743bc6db6776150cc29ae960ca7eda2b66dc681532f3aeee4' 
  AND token = 'sKqQgpwryJIbWaSbIsuoQQb6IVmmpQgGqHOV5oSO8lM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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