SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a2f0001198864ecd45ab45a0b9b68b2a3bcfcc75c1369830e1dc9afa42ed08d' 
  AND token = 'HZvrKmsM9j3hUBYGzoWLKb+3Fi1yJ6ixXIPzfb6OHVw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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