SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8d62abb496b1ff3fe7e6e8d0e7f85d40fc1c15ed461453385e9fcd2d2059965e' 
  AND token = 'SpmbipVigWElxwYCfnreGegWyAvQdHbJtvzMNgqs08o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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