SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b7527795bdff3b6a7dabe48ff9eb079d61f285a3c919b1da0e06b95067bfcfc' 
  AND token = 'l2a3907S3wZ5+FSeLSzUx8/zyMKVdsrGrsis5f3nlYQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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