SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f5f9ba6a5d910174610265e3b192b5fc53aa2a1e59c8bc8009c52bc85f64ce3d' 
  AND token = 'GgPLrO3tQgoPwbIyaZkMRYX7EmXJ4WDk2fCTfGYFbyw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}