SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b6d30bfe0e91ccfcc5ff82bee6a3c4d3520aa7780d0a00e131b689a17f9d3b1e' 
  AND token = '7xYQjDRk+xknWsvtL9Rd481h2ygj4fiNUcbz82An6gs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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