SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '94bfc726bf2ad0aec13083f330543047671e151bb1b1121ea838fc14a89c78b5' 
  AND token = '2W9FLGJHjJNItWwkkTtqJTlvjlRemLldhjciB2z+x1s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00068

JSON explain

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