SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4306f9bf3d4eaf410dbfca49906cb2bec1c8dc1d5a7345f2a25236b7fd8d69ab' 
  AND token = 'Cm1GV0nGWOCe04sQ3YCA0KPzD9TPVWOnQCTIBYi6iRE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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