SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e035b4a1f1beafa59fad7601248250ce0080b1ceaa5aff325ae9682ba19d393f' 
  AND token = 'K2hQ6ShLyEavIhxlLaIx/LDMwI6WjY8IlEk+bq3vPXc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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