SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dbfa1d72d97b51f5df5490a70207c38878e184c095e7d07fd685b85cd2f336ea' 
  AND token = 'iBdSNUP5lV+joWGVeyt4vPorzhoKfMDkQLNnMIzJbxg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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