SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c0f03aa398a9eca28f762967db6f8068c92bdd2cd484d38855fa3d60bfbfdf60' 
  AND token = 'fDgEa5FD2G5KIVkSuqZSvh1z0CZ2aKsHw/XjZnfkS1U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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