SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11f69485aa933214d3a34ab756d8cd98c795de873f0ce4116578503fcad4bcd0' 
  AND token = '30l7FlBjXsvJ8ovVGHTUV4ZRJqcGCKusUvPb5MyvSoE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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