SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd6abea621592e6390d806e8cc93df53823eb364005e2fee8bb2b5a499cfae745' 
  AND token = 'TJ/GGjJvdfIIEGS37BiUEP4a9tFaIVHOQCZTWO5COug=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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