SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a3ac2bcb10c0fb7fbfd92bfefefb43e04f76671e3403ac234bdd11620c62a1f0' 
  AND token = 'c425bCNSgZsEmWwg4xvx3DI12M8ArGHnJHVegdfZkIs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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