SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '717306dce25daf394b2dbe4bc82ab72fee90c6822e8a6c1d4521064ef867ac1f' 
  AND token = 'mFmOoOuSoCzqvk/Mt1z/eZku6AVXDbYBwH5ehT1Qpzg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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