SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fac0674a383a0b625fa5a99234001b79f699242ed7ad6ee75aff271c96195fd7' 
  AND token = '8kSo+xeCVAPaFKS3+KPrEer4j61wcVt719tDQlJfL0A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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