SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fbd118ce85244af1ef1f2c6f1fa127eb1de77be45069d5ef69e52087bea31387' 
  AND token = 'ecj3PUc/eFswz6e39ThAeJsKaKjRBLtVtMsw+Vsw5cM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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