SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b3217ce224fdd53f4dfb1fa99df4c861c976c458f96eb345f4ac928fdc7e5945' 
  AND token = 'HT5+DAU1kGpzpnGO7Jb7NWpw3GzwavBs/9CBxwvy8F8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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