SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '692197169366d7d8f0f96a41266e5672518bfc06158a9d82afab314c2aaddf48' 
  AND token = 'O2bxTZRLuLCTKNVRNeT2IS979Ic8ksw9uHs436F0WKQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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