SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '29a157813eb36a007c1d1495e7311935e898a73ae9902f7721b11dfd45a728b1' 
  AND token = 'vSQXag651q6p5P4IxAxdn9NLT/lU/vm7rdv2vOMjPpU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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