SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6edbb08dd98224f273c9a396cd5379a067ca8b106c4c683b46773a39cf3abf5f' 
  AND token = 'zQHcbdm8oqsq3Q0VUcygG4RPlN5Cohh0Li7wY6LOquQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00063

JSON explain

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