SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ddb70431663fd2b255bd68bdbc441b3cc62c02eb66af928e57d7c0bc18c8abc7' 
  AND token = 'zKkmqZxDZ64pGU63Tm3mRJVU1kl+4xra+7ShgPOr4/g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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