SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd107eaa5306feadfffd30abca802855b0801a51964b880d9ee9685105614d9a4' 
  AND token = 'ecxu+7hBdmhy7unBI1bzJIlv/uFTfEAfc0I2wWT3ddw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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