SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '91aae65affcdeb82e71c69062620ee860eb20a42561f680cda469f4b71c1bdbf' 
  AND token = 'XA4WB6LC4H6YQgfc0Px4mjOBJmoM6Mnw9UBjktqHUSM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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