SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32394c25a2f23c055d3dfabe8c3ebb888bda6c96db9a26ca462b8e298435c5a8' 
  AND token = 'oFOXDygJELadMFwNaj57DqxmxThAecafJCwRRzdrl80=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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