SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eeb5121233cd1ce66d93924b8975ae7e3348c45e6c112aa29297eeff0598c4a9' 
  AND token = 'wtx3M6coiw9L+2GkoQbvezxIR0NV+KuQvE6khl1KQs8=' 
  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"
    }
  }
}